Suppose a case where a pedestrian has a collision (defined as a first-time collision) with a front end part of a vehicle such as a front bumper. In such a case, the pedestrian may fall onto the vehicle so that a head part or a chest part of the pedestrian has a collision (defined as a second-time collision) with the body of the vehicle.
A technology for reducing a damage of a pedestrian having such a second-time collision is known as a system that operates a protection device such as an air bag inflated towards a predetermined range outside of the vehicle in response to the detection of a first-time collision with a pedestrian (for instance, Patent literature 1). Such a system can reduce an impact enforced to the pedestrian due to the second-time collision.
Protection devices, which protect a pedestrian from a second-time collision, include a pop-up hood apparatus that raises the back of the hood, in addition to air bags inflated in various regions such as the windshield, the pillar part, and the cowling top.